Name: Rajib Kumbhakar
Affiliation: S. N Bose National Centre for Basic Sciences
Conference ID : ASI2022_757
Title : Photometric Variability in Young Brown Dwarfs to Probe their Atmospheric Properties
Authors : Rajib Kumbhakar and Soumen Mondal
Abstract Type: Poster
Abstract Category : Stars, ISM and Galaxy
Abstract : Photometric variability studies of very low-mass stars (VLMs) and Brown Dwarfs (BDs) are an important tool to probe the physical nature of their atmospheres. Photometric variability in these dwarf is due to the presence of surface features like magnetic spots (strong magnetic fields) or dust clouds, which cause optical modulation as it rotates, and it is possible to measure the period of rotation of an object from its light curve. The time-series photometric variability is a key probe of atmospheric inhomogeneities in VLMs and BDs. BDs are known to be rapid rotators (priod~ hours to days), so the rotation modulation of their light curves gives information about surface features such as magnetic spots or dust clouds, which provides an opportunity to measure the period of rotation in these dwarfs. However, it is very challenging to detect their variability amplitude, which is the order of a few tens milli-magnitudes. We have taken optical I-band time-series photometric observations on a few BDs and VLMs in the Taurus star-forming region. From our preliminary analysis of the observed data in the I-band on CFHT Tau 6 and CFHT Tau 8, we found that CFHT Tau 8 shows significant periodic variability, and we estimate a rotation period of 6.6 hours. While CFHT Tau 6 shows no significant variability with a given accuracy with the observed time-series I- band data.